House



(No Model.) 2 SheetsSheet 1' H. H. WESTINGHOUSE.

- STEAM ENGINE. N0.340,022. Patented Apr.-13, 18865 2 Sheets-Sheet 2.

(No Model.)

H. H. WESTINGHOUSE.

STEAM ENGINE.

Patented Apr. 13, 1886.

INVENTOR,

WITNESSES:

WI 41 N. 14167 N. PETERS. Phulo-Li'hognphu. Wnhinglon. D. C.

UNTTnn STATES ATENT FFICEO H. HERMAN VVESTDTGHOUSE, OF PITTSBURG, PENNSYLVANIA, ASSIGNOR TO THE WVESllXU HOUSE MACHINE COMPANY, OF SAME PLACE.

STEAM-ENGlNE.

EEPECEE CATIUN forming part of Letters Patent No. 340,022, dated April 13, 1888.

Application filed January 18, 1886. Serial No. 188,822. (No model.)

T at whom, it may concern.-

Be it known that I. H. HERMAN ESTING- HOUSE, residing at Plttsbnrg, in the county of Allegheny and State of Pennsylvania, a

citizen of the United States, have invented or discovered'certain new anduseful Improvements in Steam-Engines, of which improvements the following is a specification.

In theaccompanying drawings, which make IO part of this specification, Figure 1 is a vertical longitudinal section taken through the centers of the cylinders of an engine embodying my invention, and Fig. 2 avertical transverse section at the center of the low-pressure cylinder.

My invention relates to iinproven'ients in single-acting steam-engines, more particularly those of the class in which two or more cylinders are connected to and open at one end into a closed crank case or chamber, within which a crankshaft, to the cranks of which the pistons of the cylinders are coupled, is adapted to rotate in a bath of lubricatingliquid, as is exemplified in Reissued Letters I Patent No. 10,603, granted and issued to The \Vestinghonse Machine Company, as my assignee, May 26, 1885.

The object of my present invention is to provide in a single-acting engine means for properly cushioning the downward stroke of the piston and imparting an initial upward tendency thereto, and for maintaining the piston in proper relation to its crank by the exertion of a suitable retarding action upon the piston toward the terminal of its upward stroke; also to provide in a compound singleacting engine embodying the characteristic features of the type above indicated, as is in stanced in my application Serial No. 174,878, o filed August 20, 1885, suitable means for preventing the ejection of lubricating material ironi the crank-case by reason of unequal displacement of the pistons.

To these ends my invention, generally stated, consists in a singleacting cylinder having a closed internal cushion-chamber on the side of its piston opposite that which receives steam-pressure, and in the combination of a high-pressuresingleacting cylinder and a lowpressure single-acting cylinder of larger diameter, each located above a closed crankcase adapted to contain lubricating material, and having pistons connected to cranks on a shaft therein, a trunk or tubular extension fixed to the low-pressure piston and corre- 5 sponding in diameter with the high-pressure piston, and a head closing the inner end of the low-pressure cylinder and provided with a sleeve or casing inclosing the trunk of the low-pressure piston.

The improvement claimed is hereinafter fully set forth.

My invention is herein exemplified as applied in acompound single-acting engine, the general structural features of which correspond, substantially, with those of the engine set forth in my application Serial No. 174,878, before referred to, sundry of which, being either heretofore patented or constituting part of the subject-matter of said application, are 7 not herein claimed. A high-pressure cylinder, 1, and a lowpressure cylinder, 2, of larger diameter, between which is interposed a valve chest or chamber, 3, are secured upon the top of a closed crank-case, 5, which constitutes the bed or support of the engine, and likewise serves as a tank or receptacle for the lubricating material of the crank-shaftjournals and crank-pins, the same being preferably a mixture of oil and water, which, by so the rotation of the shaft and cranks, is in the operation of the engine constantly sprayed over the parts-to be lubricated. Access to the interior of the crank-case is afforded, as desired, by a reniovablc bonnet, 6, secured to one side of the crank-case over an opening therein.

The high and low pressure cylinders 1 2 are fitted, respectively, with pistons 7 8,

which are coupled by connecting-rods 9 9 to 0 crank-pins set oppositely or at angle of one hundred and eighty degrees upon a pair of double cranks, 10 10, formed upon a crankshaft, 4, having journals mounted in bearings in the ends of the crank-case 5, and carrying one or more balance-wheels, 42, and a beltpnlley, 43. Steam is supplied to the valvechamber 3 from vthe boiler by a steam-pipe secured to a flange or nozzle on the side of the valve-chamber, and is admitted to and exhausted from the upper ends of the high and low pressure cylinders 1 2 by a main or dis-= tribution valve, 12, which is coupled to an eccentricrod, 19, secured to the strap 20 of an eccentric mounted on the crank-shaft 4, :05 said eccentric being preferably adapted to be moved transverselyto the crank-line,so as to ceeding upward, stroke;

vary the travel of the valve in correspondence with variations of pressure or resistance, or both, by a suitable centril'ugal governor connected to and rotating with a disk or carrier, 25, fixed upon the crank shaft. The distribution-valve 12 primarily admits steam from the valve-chamber to the space above the highpressure piston 7 through a port. 74. thereafter exhausts the steam. which has efl'ected the downward stroke of said piston, through the port74, the tubular body of the valve, and a port, 14, into the space above the lowpressure piston 8, and finally exhausts said steam,after it has effected the downward stroke of the low-pressure piston, through the port 14 and through exhaust-ports in the valve to an exhaust-pipe leading to a condenser or to the atmosphere. v

The operation of an engine as above de scribed has failed to be wholly satisfactory in practice, when the lower ends of both the high and low pressure cylinders are open to the crank-case, by reason of the fact that the unequal displacements of the larger and smaller pistons 7 and 8 in their traverse act to force the lubricating material out of the crankcase. and, further, by reason of the absence of means for properly cushioning the low-pressure piston at the lower terminal of its stroke and maintaining its due relation to its crankpin at its upper terminal. These objections are fully and satisfactorily obviated by the following construction: The lower end of the high-pressure cylinder 1 is left wholly open to the crankcase, and the lower end of the low-pressure cylinder 2 is closed by a tight head, 15, having a central cylindrical sleeve or casing, 16. which incloses a trunk or cylindrical projection, 17, tormed 'upon or secured to the lower side of the low-pressuripiston Sand corresponding in diameter with the high-pressure piston 7, said trunk carrying the pin to which the upper end of the connecting-rod 9 of the low-pressure piston is coupled.

The trunk 17 and sleeve 16 are made of such length that a portion of the trunk shall be incloscd by the sleeve at all points of the stroke of the piston 8, or, in other words, that the space or cushion-chamber 18 around the trunk and between the lower side of the piston Sand thehead 15 shall he at all times closed to the crankcase. such space being obviously equally closed to the steam-space above the piston. it will therefore be seen that as the displacement of the lowpressure pistontruuk 17 is equal to that of the highpressure piston 7 the lubricating-material in the crankcase will be undisturbed by the movements of said members, and that the air entrapped within the cushion-chamber'IS will be compressed therein during the lower hall of the downward, stroke of the low-pressure piston 8, thereby cushioning said piston at its lower terminal and im- .parting to it an initial impetus for its suc- During, the upper half of the upward stroke of thelow-pressnre piston the retarding influence of the air in the cushion-space under the exhausting action of said piston acts to cushion the piston at its upper terminal and maintain itstnormal con nected relation to its crank-pin in tending to effect its downward stroke. 7

' For the purpose of relieving any excess of pressure in the cushion-chamber 18 and admitting ot' the discharge of water of condensation due to leakage of steam thereinto, the cushion-chamber is provided with a check or relief valve, 21, which opens outwardly, and

"is loaded by a spring or weight in accordance with the pressure proper to be maintained in the chamber.

I claim herein as my invention 1. ln a singleacting compoundengine, the combination of a crank-case a high pressure cylinder and a low-pressure cylinder of larger diameter connected to said crank-case. and pistons fitting said cylinders and open to the crank-case through surfaces of equal area on their sides adjacent thereto, substantiallyras setforth.

2. In a single acting compound engine, the combination of a crank-case, a high-pressure cylinder and a lown'essure cylinder of larger diameter connected to said crank-case, a. trunk fixed to the low-pressure piston on the side adjacent to the crank-caseand corresponding in diameter with the high-pressure piston, and a head closing the crankcase-end ol' the lowpressure cylinder, and provided with a sleeve or casing int-losing the trunkfof its piston. substantially as set forth.

3. In a single-acting engine, a cylinder having a closed internal cushion-chamber on the side of its piston opposite to that which receives steam pressure, substantially as set forth.

4. In a single-acting engine, the combination of a cylinder and a piston working therein and having a trunk on itsside opposite that which receives steam pressure, said trunk passing through a head in the adjacent end of the cylinder and forming with the piston a closed cushion-chamber therein, substantially as set forth.

' 5. In a single-acting engine, the combination of a cylinder, a piston working therein and having a trunk on its side opposite that which receives steam-pressure, said trunk passing through a head in the adjacent end of the cylinder and forming with the piston a. closed cushion-chamber therein, and a check or relief valve controlling a passage leading out of said cushion-chamber,substantiallyas set forth.

In testimony whereof I have hereunto set my hand.

H. HERMAN VVESTINGHOUSR. 

